1. Field of the Invention
The present invention relates generally to an audio signal mixing system, and more particularly to a novel system which mixes additional signals with the stereophonic signals.
2. Description of the Prior Art
A microphone mixing circuit has been proposed which can reproduce a live singer's voice through a speaker with background music from, for example, a recording. However, with prior art microphone mixing circuits, the singer's voice from the recording and the live singer's singing voice appear localized at the center point between left and right speakers and hence the sound image of the live singer is superimposed on the sound image of the recorded singer at the center. In this specification "live singer" indicates that the performer is physically present and performing and "recorded singer" refers to sound from a recording.
To avoid this drawback, circuits which attenuate the reproduced signal from the record which amplify the signal from the microphone have been considered. In such methods or circuits, however, the music from the record will also be attenuated which is undesirable.
A method has been proposed in which the center vocal signal or monaural signal contained in the stereophonic signals is eliminated and a signal from a microphone is added on to the stereophonic signals. With this method, the sound of a user and the sound from a record will be reproduced from the same speaker. In this method, however, the singer's voice on the recording will be entirely eliminated and it is nearly impossible to compare the user's voice with the singer's voice.